Every aspect of a controlled explosion has to be carefully planned. This means selecting the right tools and equipment for the job, as well as choosing the best explosive to deliver the desired end results.
The blasting cap may not be the largest component in the explosive system, but it is one of the most important. It is, in fact, the primary explosive device that is needed to get the secondary explosive material, such as ANFO or dynamite, to explode. As these secondary explosive materials need to be designed to detonate only with the use of the detonator, the cap becomes a critical component to initiating the explosion.
Types of Detonators
Detonators, or blasting cap, can go from the very basic and traditional to very modern and designed with several security and safety features. Different types of detonators may be easier or more challenging to work with, and some are designed for specific use with different blasting systems.
Pyrotechnic
These are the oldest type of detonators and they require an output explosive, a primary explosive and an ignition mix be placed in that order into a tube closed at one end. Into the open end, the fuse is inserted and the tube is crushed to hold the fuse in place.
Fuses can be adjusted to provide specific types of delays, and they are ideal for use when other fuse options may be cost ineffective or when there are high levels of specific electromagnetic interferences in the area.
Electric Detonators
First used in the late part of the 1880s, electric detonators use electricity to replace the burning fuse. This allows for pre-programming of the detonation, so it was possible to structure and sequence the explosion to enhance the end result.
However, electric detonators are sensitivity to outside sources of electrical current as well. This can cause unplanned detonation in the presence of electromagnetic fields, static electricity, radio frequencies and high levels of heat.
Non-Electric and Electronic
These blasting cap designs were developed in the 1960s and used a shock wave for detonation, eliminating the concerns with the use of electric detonators. These are widely in use today as a safe, stable and reliable detonator in a wide range of soil and subsurface conditions.
Offering state of the art technology, the electronic detonators provide for full computer control of the explosion sequence down the millisecond. These operate only with specific blasting machines with safety verification and protocols to eliminate many of the safety issues in detonators of the past.